If you try to imagine an American-born David Hockney, you might turn to painter-designer-playwright-director William Leavitt, now approaching his 70th birthday, whose artworks on the theme of the theater are the subject of a retrospective at downtown's Museum of Contemporary Art, "William Leavitt: Theater Objects," through July 3.

There's an eerie incandescence to the paintings and sculptures in the exhibit, a trait you also see in most theater sets if you subject them to scrutiny — that of being in a world simultaneously real and unreal, an enclosed world that's at the same time a cauldron of artifice. So in that world, actors — that might be us — can fully invest in the reality of the environs while being at least partly cognizant (unless we're "method" actors who "live in every moment") that the lines we're speaking are part of an artful charade, if the play's any good, and an artless one if it's not. In one piece, you gaze upon a tartly decorated three-dimensional living room only to spy, at just the right angle, that the whole thing is held up by a diagonal wooden brace — illusion and disillusion.

This is all a variation on the effect evoked by Hockney's paintings of Southern California swimming pools, where you have to squint to look into the water and where you might find the bobbling reflections of a subject similarly squinting. Or the windswept landscape of the Joshua tree–spiked Pearblossom Highway, somewhere outside Little Rock, where hyperrealism has a dustup with a mirage or two.

Another painter who may come close to Hockney's and Leavitt's ever-so-tender breaches of realism is Carl Ramsey, who, like Leavitt, has lived in L.A. most of his life and dedicated the body of his work to the place. Ramsey currently co-curates (with Richard McDowell) the Optical Illusion Gallery near MacArthur Park.

One of Leavitt's paintings, Spectral Analysis, is actually a set for a one-act play — one that he wrote — not coincidentally called Spectral Analysis, first presented at Houston's Contemporary Arts Museum in 1977, and presented in a Santa Monica space some 20 years later. It was performed over the weekend at MOCA in a gallery where the set had been installed.

As theater sets go, it's an unprepossessing construction, which is the point. On the right side of the stage sits a small, cream-colored leather couch. Behind it, a bare, lighter cream wall that's obviously a flat, as the rigging holding it up is exposed. On the other side of the stage stands a kind of hospital partition — cheesy curtains dangling from a portable frame. It's what they use to give a patient a bit of privacy.

Suspended over all this quasi-homey sterility hangs a vintage early-'60s chandelier that Charles Phoenix would make a big deal about were this one of his SoCal retrospective slide shows. From its core emerge coiling explosions of copper-plated arms, each culminating in a small electric candle. It's a bit like seeing Medusa's snake hair trying to pass for a lighting instrument, which somebody, at some time long ago, once imagined as futuristic chic. Furthermore, though illuminated, it barely lights a single object on the stage, which fulfills the definition of kitsch.

There are lighting instruments in the gallery, and they are aimed at the set, but not at the actors (the excellent Maribeth Monroe, Christopher Sweeney and Theresa Gumprecht), who perform a verbal dance of domestic and metaphysical estrangement that's the crux of Leavitt's script.

What happens when you get a set designer writing plays is actors who are largely conceived as part of the set. Their job is to fill it, so to speak, and to underscore and overscore the properties of life's ambivalence that the set aims to evoke. There's no follow-spot here, nobody bursting into "There's No Business Like Show Business." In place of flippancy there are perhaps shadows of irony. There are shadows everywhere.

The one light source that grabs focus shines from a video monitor next to the couch, and between the two walls. On the screen, we see the image of a diamond spinning, eternally, a kind of gyroscope. The lure of a shiny object, perhaps something of value, to be purchased, is a mirage that might just as well have appeared in one of Hockney's desert scapes. In the play that emerges, depicting the obvious vacuousness of the characters' lives, the petty, almost violent arguments, the ennui, that spinning diamond is a kind of taunt.

The play is constructed as a series of short scenes between Woman (Monroe) and Man (Sweeney). The somewhat oblique, Pinteresque repartee recalls the writing style from the Padua Playwrights, a school of local scribes that includes Murray Mednick, John Steppling, Sissy Boyd, Guy Zimmerman and Kelly Stuart. This would-be dialogue sparks from the prior line, as though by rote, until an unchallenged non sequitur reveals not only a hidden mental state but also a layer of absurdist truth.

Woman: Did you clean the pool today?

Man: Me, why?

Woman: I wanted to swim.

Man: Well, it's not that dirty.

Woman: I can't stand all those big leaves floating around in it.

Man: Why don't you do it then?

Woman: I can't. I'm going to the airport again.

Man: Well, I have to work. (long pause) Aren't you getting bored with Marvin and his silly passion for skydiving?

Woman: Sure I'm bored, but I don't want him to go by himself.

Man: There's always a victim.

Woman: I'm not going to say any more about it.

Man: Yeah, those topics.

Woman: It's going to work out, just wait and see.

Man: I think we should get out of here for a while.

Woman: Oh! Yes. Yes. I want to take the Concorde.

Man: You know, I hear it's really a very small plane.

Woman: At least you don't age quite so fast at those speeds.

After each scene, a new vertical strip of color appears on the hospital curtain — in physics, "spectral analysis" refers to the physical properties that can be discerned from differing wavelengths of light. In the play, the Woman, a real estate agent, refers to the files she keeps in order to keep business orderly. Something is being filed, as life slides by. I should mention there's a second woman (Theresa Gumprecht) who makes a brief appearance, slouching on the couch, before exiting.

Call it local existentialism, tautly performed and staged, directed by Leavitt and Rob Sullivan. So much has changed since this play's 1977 premiere — in technology, in the way we think, and think of ourselves, our place in the world — and yet the play nonetheless strikes eternal verities that we've almost stopped dwelling upon, in our haste to read our next email or tweet.

After the performance, I strolled into the Geffen gallery down the hall, facing down paintings by Joan Miro and Roy Lichtenstein and Mark Rothko. And I felt as though I'd just taken a 70-year walk around the block.